Temperature gradient-based high-cell density fed-batch fermentation for the production of pyruvate oxidase by recombinant E. coli

Effect of temperature on synthesis of clavulanic acid and impurity substance G during fermentation by Streptomyces clavuligerus

Effect of temperature on synthesis of Clavulanic acid (CA) and impurity substance G during fermentation by Streptomyces clavuligerus were investigated. Results show that fermentation at 24 °C is the most favorable for CA synthesis though the fermentation duration was 20-30 hours longer than fermentation at 26 and 28 °C. Meanwhile, the impurity substance G was only 110 mg/L in the end broth of fermentation at 24 °C, which was significantly lower than 148 and 180 mg/L of fermentation at 26 and 28 °C, respectively. Correlation of specific growth rate and CA synthesis was statistically analyzed based on data of 10 batches of industrial fermentation. Two temperature-shift strategies were investigated in 50 L fermenter. Fermentation with 26-24 °C temperature strategy achieved 5097 mg/L CA titer, meanwhile the fermentation duration was shortened 24 hours comparing with fermentation at constant 24 °C. Fermentation with 26-24 °C control strategy was validated in a 60 m³ industrial fermenter, in which 4960 mg/L of CA was achieved while impurity G substance was decreased to titer 65 mg/L from 200 to 300 mg/L of normal production.

Control algorithms and strategies of feeding for fed-batch fermentation of Escherichia coli: a review of 40 years of experience

Fed-batch cultivation is a well-known type of submerged fermentation that is frequently used in manufacture of recombinant proteins and various kinds of enzymes, owing to its ability to produce products with high concentrations and high efficiency. In fed-batch culture, several issues must be considered; most of them are also presented in batch culture. However, feed flow rate calculation only corresponds to fed-batch fermentation and its value has a significant impact on productivity, efficiency, final concentration of product, formation of by-products, and viscosity of the culture. From this background, the present review article is an effort to gather the information on feeding strategies for fed-batch cultivation of Escherichia coli, which is a well-known microorganism in the production of recombinant proteins and industrial enzymes, especially for therapeutic applications. Moreover, this review is an aid to comprehend and compare the fundamental concept of different feeding strategies and their advantages and drawbacks.